# Statics via Lagrangians

1. Jul 22, 2010

### least_action

Is it possible to do statics using lagrangians? (specifically building up a compound shape like a bridge from constrained point masses). Where could I see an example of this?

2. Jul 22, 2010

### fobos3

Yes, just put the Lagrangian equal to the potential energy. However I think you will find that, if you have an equilibrium the potential energy is at minimum more useful. For example consider the cantenary.

$$V=\int_C my\,ds$$

Now if you use Lagrangian mechanics you would be minimising $$\iint_C my\,ds\,dt$$ instead of $$\int_C my\,ds$$

3. Jul 23, 2010

Thank you!